White Saturation Test

How this test works

Look for subtle bright patches that remain distinct from the white background.

1. Prepare the display using the checklist below.
2. Select Start test and allow fullscreen mode if your browser asks.
3. Use the arrow keys, on-screen controls, or click the pattern to move through the test.
4. Exit the runner and save a local observation if useful.

Before you begin

• Avoid direct glare
• Disable dynamic contrast
• Start from the display's standard picture mode

What to look for

• Which bright patches remain visible
• Color tint in highlights
• Abrupt clipping near white

Look for detail close to white

The test shows numbered light-gray patches on a white field. From a normal viewing distance, look for subtle differences among the brightest steps without requiring every patch to stand out strongly. When several shades merge into a single white area, highlight clipping may be occurring somewhere in the active display path. Begin with the monitor’s standard picture mode and ordinary brightness. The white field can be tiring on a large bright display, so lower brightness to a comfortable level and keep the check brief, especially on an OLED panel.

The relationship between nearby bright shades matters more than the exact number of patches you can read at one glance. Compare the same pattern after changing just one setting, such as contrast or a picture preset. A mode that makes every patch very obvious might alter the intended tone scale; a mode that hides them all may be clipping. This visual check cannot establish a calibrated white point, HDR peak brightness, or whether the panel meets its advertised luminance specification.

Distinguish clipping from glare or tint

Direct room reflections can conceal pale patches. Move a lamp or change your viewing angle before concluding that the monitor lost highlight detail. Dynamic contrast, vivid modes, and automatic brightness can also change the result while you inspect it. Disable those features for a controlled comparison, then test again under your normal settings. If a white field looks pink, green, or blue, note whether the tint covers the entire panel or only a region; that points toward a different visual question than simple highlight clipping.

Check that the browser window remains on the intended display if you have a multi-monitor setup. Different displays can have different color profiles, brightness, and operating-system HDR settings. This pattern is an SDR browser check. It does not create a calibrated HDR signal merely because the monitor advertises HDR support. If highlights in normal photos or video look unusual, compare the material in another app or picture mode and record the context instead of treating the web pattern as a universal verdict.

Compare related tone tests without mixing their purpose

Use the gradient test if you see distinct bands across a long transition. Use the black level test when shadow detail rather than highlights is missing. A color cast on neutral fields belongs with the monitor color or uniformity check. Those pages share some display settings but answer different questions. Keep your notes specific: which bright patch values are visible, at what brightness and picture mode, and whether the same issue affects everyday content. A clear observation makes it easier to choose a useful follow-up.

This page cannot measure maximum luminance, contrast, color accuracy, or tone mapping. A light meter or colorimeter with a suitable method is needed for objective values. It also cannot tell you which component caused a clipped highlight: source content, browser processing, signal range, graphics settings, and display processing all contribute. Treat the pattern as a quick visual comparison between modes, not a reason to maximize brightness or to leave a static white screen running for a long period.

Frequently asked questions